Correction: An earlier version of this editorial incorrectly reported that the office of the D.C. chief financial officer carries a four-year term. The CFO serves a five-year term. The version below has been corrected.

DISTRICT MAYOR Vincent C. Gray’s letter last week questioning the revenue projections of the city’s chief financial officer wasn’t intended, in the words of his spokesman, to be a “big deal,” but rather simply a request for more information. That’s reassuring, because the last thing the District needs is for this critical office to become a target of ill-advised political pressure.

Whether Natwar M. Gandhi has been overly cautious in his projections may be open to debate, but there is no questioning that the District’s robust fiscal health is the direct result of having an independent chief financial officer who can’t be cajoled or bullied into telling officials what they want to hear.

In what The Post’s Mike DeBonis called “an unusual and possibly unprecedented move,” Mr. Gray (D) questioned as “unrealistically low” the revenue projections released by Mr. Gandhi. The letter, which became public shortly after it was delivered to Mr. Gandhi, notes a number of trends, including increasing population and falling unemployment, that might suggest higher revenue. The letter cited “seemingly contradictory information” in asking Mr. Gandhi for additional data to back up his projections that forecast a budget gap that would have to be closed for fiscal year 2013.

Fresh in Mr. Gray’s mind is the city generating a $240 million surplus in fiscal 2011, a budget year that began with tax increases and spending cuts, including furloughs for city employees. The prospect of having to implement similar measures for the 2013 budget is, Mr. Gray wrote, “extremely unwelcome.” No doubt the job of the mayor and D.C. Council would be easier if Mr. Gandhi adjusted his revenue estimates.

As anyone who knows Mr. Gandhi will attest, that’s not likely to happen. For his part, Mr. Gandhi has to take into account potential radical reductions in federal spending in January, if congressional “sequestration” comes into effect.

So why did Mr. Gray write the letter? It comes as the mayor must decide whether to reappoint Mr. Gandhi to a third five-year term; his current term expires in June. If, as the administration said, it was to give the public more confidence in the numbers, by making the process more transparent, it likely had the opposite effect. If it was to make Mr. Gandhi the fall guy for decisions to bring spending in line with revenues, people should be mindful of the time, not too long ago, when wishful thinking and overspending led to imposition of a federal control board.

As one astute D.C. observer said, “Mr. Gandhi is cautious; the mayor should want him to be cautious.”